Red Hat Enterprise Linux 7 (RHEL 7) is the first major release of RHEL to allow in-place upgrades from the previous RHEL major release (RHEL 6). An in-place upgrade offers a way of upgrading a system to a new major release of Red Hat Enterprise Linux by replacing the existing operating system.
This RHEL 6 to RHEL 7 upgrade procedure is fully supported if your Red Hat Enterprise Linux system meets the following criteria:
Latest Red Hat Enterprise Linux 6: Before upgrading to the latest RHEL 7, you must start with RHEL 6 and update your system to have the latest RHEL 6 packages installed. (This is covered in the procedure below.)
All Server editions (except x86): All server editions (except x86) of Red Hat Enterprise Linux 6 can be upgraded with this procedure. Upgrades of RHEL Workstation and Desktop systems are not supported. Upgrades for the POWER architecture is supported. SEE TABLE ABOVE. Upgrade from 32-bit architecture is not supported.
Limited package groups: The upgrade process handles only the following package groups and packages: Minimal (@minimal), Base (@base), Web Server (@web-server), DHCP Server, File Server (@nfs-server), and Print Server (@print-server). Although upgrades of other packages and groups are not supported, in some cases, packages can be uninstalled from the RHEL 6 system and reinstalled on the upgraded RHEL 7 system without a problem. SEE TABLE BELOW.
The supported use cases for upgrading RHEL 6 to RHEL 7:
SupportedUnsupportedSource to Upgrade The latest RHEL-6.X RHEL 6.4 and earlier
File Systems Like-file system upgrades
For example ext3 to ext3, ext4 to ext4, xfs to xfs Unlike-file system upgrades
For example ext4 to xfs
GNOME, KDE None All GNOME, KDE installs
Packages/Groups Minimal (@minimal)
Base (@base)
Web Server (@web-server)
DHCP Server
File Server (@nfs-server)
Print Server All others
Virtualization KVM, VMWare Microsoft Hyper-V (coming soon)
Red Hat Software Collections Using tested process All others
High Availability None All
The upgrade procedure consists of the following basic steps:
Prepare for Upgrade: Make sure your system is backed up and up to date before beginning the preupgrade.
Install the Preupgrade Assistant: Enable the required repositories and install the preupgrade packages.
Run the Preupgrade Assistant: Check your system for upgrade issues before running the actual upgrade. No changes are made to your system and you can repeat this step until all issues are dealt with.
Run the Upgrade: Perform the actual upgrade.
Provide Feedback: Create a debug log to send to Red Hat in case there are problems.
实践步骤核心目标为格式化/分区，保留其它文件系统，做好相应备份重装RHEL7
生产环境当前系统版本为RHEL6.7，推荐升级至RHEL7.1或者更新的版本
通过RHEL7.1的ISO引导至INSTALLATION SUMMARY
DATE & TIME设置为Asia/Shanghai timezone
LANGUAGE SUPPORT添加English(United States),简体中文(中国)
SOFTWARE SELECTION设置为Server with GUI
UBSTAKKATUIB DESTINATION分区选择I will configure partioning，点击DONE
找到现有系统中的/分区，选中后在右侧勾选Reformat，Mount Point设置为/，SYSTEM其它分区SWAP,/boot,/usr,/tmp,/var参照同样操作，DATA数据分区不动，点击DONE
Begin Install
安装结束后恢复备份数据
恢复原有网卡配置项和IP地址
恢复主机名/Hosts/Profile
恢复fstab分区检查数据一致性